1. Field of the Invention
Various embodiments relate in general to semiconductor devices and to processes for fabricating semiconductor devices. More particularly, various embodiments relate to semiconductors having a passivation layer including one or both of an ultraviolet radiation (UV) blocking layer and a compressively stressed, crack-preventing layer and also to processes for fabricating such semiconductor devices.
2. Description of Related Art
As device geometry has continued to shrink, dimensional requirements of devices become more exacting while the aspect ratios of etching or gap filling rise. Plasma process technology is indispensable for ULSI fabrication that meets these demands. Examples of plasma process applications include plasma implantation, plasma sputtering, physical vapor deposition (PVD), dry etching, and chemical vapor deposition (CVD), for example, plasma assisted CVD, plasma-enhancement CVD, and high-density plasma CVD. During plasma processing, photons are generated with wavelengths in and above the UV spectrum.
Passivation layers are typically deposited, using plasma processes, over the top of the wafer after the final patterned conductor layer has been made. The passivation layer is used to protect the device structures from mechanical damage, such as scratching, as well as chemical damage, such as from moisture and other contaminants. With some types of devices it is important that the passivation layer permit the passage of UV to the device; for example, some flash memory devices need a UV-erase process to erase the initial charge within the floating gate. However, with many other devices and structures it is necessary to prevent the passage of UV to the devices or structures, such as through the passivation layer. U.S. patent application Ser. No. 10/858,352 entitled Ultraviolet Blocking Layer discloses the use of a super silicon rich oxide layer as a UV blocking layer. The disclosure of this application as it relates to the theory, composition and process steps involved in the deposition of a UV blocking layer is incorporated by reference.